Boosting Weak Transponders

[al_madhi]

Hi ppl , wondering if anyone has tried removing the white cap of Universal Lnb and inserting a small pipe ( 3 in ) inside it would boost the weak signals .
Any thoughts you would have be greatly appreciated .

 

[n4bbq]

The best way to "boost a transponder" is to get a bigger dish or a lower noise LNBF. I have a 90cm dish and can pick up the really weak Ku band stuff pretty good. That plastic is transparent at C/Ku band.

 

[docj2005]

its sounds interesting.. but in theory does it work?

 

[n4bbq]

All the signal you are going to get at the LNB is what is reflected from the dish. If you want more signal, either get closer to the source, or add more surface area to your reflector.

 

[PilotS77]

Of course a better and/or more sensitive LNB will give you better results with the same dish.

And even thought I do not have a good scientific explanation for this, a different receiver with the same LNB and dish can also improve the reception.

I have two receivers: a Microyal MRX-900 and a Fortec Lifetime Ultra, I have one dish associated with both. When the signal is breaking or very low quality on the Fortec, without changing anything else the Microyal gives me superior and more stable picture. I am trying to figure this one out

 

[TuxCoder]

PilotS77, that is probably just due to different tuner sensitivity between the two models, or perhaps more effective FEC handling on one than the other. My two OTA digital receivers have quite different thresholds for maintaining video and audio lock.

 

[Mr Tony]

it has to be the sensitivity

I've had this happen numerous times where I can be watching the same program (same channel) on 2 different receivers and one will cut out and the other won't

Noticed it between the Coolsat and the Pansat the other day...Coolsat had stable picture and Pansat was breaking up

 

[al_madhi]

The best way to "boost a transponder" is to get a bigger dish or a lower noise LNBF. I have a 90cm dish and can pick up the really weak Ku band stuff pretty good. That plastic is transparent at C/Ku band.

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thanks n4bbq for reply

Actually Universal Lnb is designed for offset dishes only. But when comes to parabolic primary focus dishes Universal Lnb doesn't work perfectly due to wider illumination angle , and in order to make universal lnb works better is to remove the white cap and insert a small waveguide pipe down the Lnb throat .

 

[n4bbq]

You could probably pick up some copper water pipe from a hardware store and cut it for you specifics then and get a tad more rf on the LNB. Or you could build a small horn antenna on the front of this "pipe waveguide" and pick up a bit more stray RF. I'd try 3/4 inch coper water pipe to get near the frequencies of Ku band. From a quick calculation, 3/4 inch will work from 10Ghz to 15Ghz, although Ku is 12.4GHz to 18GHz.

I've never popped the plastic off the front of an LNB but I assume that is what they are already doing. It'll be interesteing to see if you come up with something.

 

[Tom Taylor]

I do have a couple of standard Universal Ku lNB's for the corotor. I have not seen one in a long time and the ones that I have were never very good. One is a Chaparral and the other is some brand made in Florida. I have found that a good 1 meter Ku dish is usually better then a standard c- ku 10 foot mesh dish when used for ku, the difference is the accuracy!!!!
We will be carying the Ivacom line or what is arguably the best Ku lnbfs available. I have had some commercial experts confirm their quality. Check my web site for availability